Medical snare

This application is a national stage application of PCT/KR2012/000371 filed on Jan. 17, 2012, which claims priority of Korean patent application number 10-2011-0007380 and 10-2011-0090231 filed on Jan. 25, 2011 and Sep. 6, 2011, respectively. The disclosure of each of the foregoing applications is incorporated herein by reference in its entirety.

TECHNICAL FIELD

The present invention relates, in general, to a medical snare and, more particularly, to a medical snare in which the expansion direction of a loop is easily rotated in an arbitrary direction in which a removable target has grown, the removable target is easily inserted into the loop so as to allow a surgical procedure to be easily performed to reduce time required for the surgical procedure and burdens of a patient and a surgeon, and free rotation of a wheel is prevented to be able to fix the expansion direction of the loop.

BACKGROUND ART

Such a type of polypectomy snare has already been known in DE 7835595. The known polypectomy snare or diathermy snare is made up of a tensile wire. The tensile wire enters a loop similar to a semicircle at a front end thereof and comes to an end there. The loop has a peak. The tensile wire is easily guided in a bushing and a corresponding pipe-shaped stopper member disposed at an end of the bushing. One of two legs of the loop is fixedly connected to the tensile wire. As a result, the loop can be displaced from a storage position at which the loop is placed in the bushing in an expanded state to a use position at which the loop is located in front of an end of the bushing by the tensile wire. The other leg of the loop which is located in the bushing is connected to a stopper moving toward a corresponding stopper in the process of extracting the loop out of the bushing. As a result, when the other leg of the loop continues to move, the loop is expanded, in a semicircular shape.

A high-frequency resection apparatus capable of supplying electric current to a snare as described above is known in DE 2951060. Here, the snare acts as an electrode. The apparatus formed in this way is used to resect abdominal tissue such as a tumor using high-frequency current according to a system for resecting a region that is located in an abdominal cavity, particularly in an intestine, and that has a tumor, for instance one or more polyps. In the region, the high-frequency current can flow between an electrode, which is intended for resection and is formed by a snare-shaped conductive wire guided into the cavity, and an outer electrode, which is fixed to skin of a patient and is disposed apart from the resection electrode.

In the event of resection, a surgeon should, typically place a loop inserted into the abdominal cavity on the polyp using an endoscope.

This conventional polypectomy snare is rotated as a whole in order to insert the loop to a spot where the polyp to be removed has grown along with an endoscope and rotate the direction of the loop in the direction in which the polyp has grown, thereby facilitating the insertion of the polyp into the loop. Since the entire polypectomy snare is rotated, there is a problem in that the surgeon cannot smoothly rotate the loop in a desired direction and a burden imposed on a wrist is increased.

For this reason, a medical snare for removing the polyp, which can easily rotate an expansion direction of the loop in the direction in which the polyp has grown and that allows the polyp to be smoothly inserted into the loop to reduce time required for the surgical procedure and to easily perform the surgical procedure, is urgently required.

DISCLOSURE

Technical Problem

Accordingly, the present invention has been made keeping in mind the above problems occurring in the related art, and is intended to provide a medical snare that allows an expansion direction of a loop to be easily rotated by rotation of a wire alone without rotating the entire medical snare.

Further, the present invention serves to provide a medical snare in which a wheel is coupled to an auxiliary pusher to which a wire is connected and is rotated, thereby allowing the auxiliary pusher and the wire to be rotated to easily switch a direction of a loop so that a removable target is smoothly inserted.

Further, the present invention serves to provide a medical snare in which engaging faces of an auxiliary pusher are engaged with an engaged hole of a wheel, thereby allowing the wheel to be accurately rotated without sliding when the wheel is rotated.

In addition, the present invention serves to provide a medical snare in which locking protrusions are inserted into locked recesses of a wheel thereby preventing the wheel from being restored to its original position by a rotational restoring force of a wire after an expansion direction of a loop is rotated by rotation of the wheel, and preventing the expansion direction of the loop from being changed.

Technical Solution

In an aspect, the present invention provides a medical, snare in which: a pusher is coupled in front of a movable handle moving along a cylindrical body in a forward/backward direction; a wire, at a front end of which a loop is formed, is connected to a front end of the pusher along an interior of a tube coupled to the front of the cylindrical body; tissue is inserted into the loop exposed from the tube by forward movement of the movable handle and is cut by backward movement of the movable handle so as to perform a surgical procedure; an auxiliary pusher having engaging faces on an outer circumference is rotatably coupled to the front end of the pusher of the movable handle; the wire having the loop is fixedly coupled to a front end of the auxiliary pusher; a wheel, in the center of which an engaged hole is formed so as to be fitted around the auxiliary pusher, is installed at a front side of the body so as to not be separated; when the movable handle moves forward/backward, the auxiliary pusher slidably passes through the engaged hole of the wheel; and when the wheel is rotated, the auxiliary pusher and the wire are rotated so as to be able to switch an open direction of the loop due to the engagement of the engaging faces and the engaged hole.

Advantageous Effects

According to the medical snare as described above, an expansion direction of a loop can be easily rotated by rotation of a wire alone without rotating the entire medical snare.

Further, a wheel is coupled to an auxiliary pusher to which a wire is connected, and is rotated. Thereby, the auxiliary pusher and the wire can be rotated to easily switch a direction of a loop so that a removable target is smoothly inserted.

Further, engaging faces of an auxiliary pusher are engaged with an engaged hole of a wheel, such that the wheel can foe accurately rotated without sliding when the wheel is rotated.

In addition, locking protrusions are inserted into locked recesses of a wheel. Thereby, the wheel is prevented from being restored to its original position by a rotational restoring force of a wire after an expansion direction of a loop is rotated by rotation of the wheel, and the expansion direction of the loop is prevented from being changed.

DESCRIPTION OF DRAWINGS

<figref idref="DRAWINGS">FIG. 1</figref> is a perspective view of a medical snare according to the present invention.

<figref idref="DRAWINGS">FIG. 2</figref> is a partial extraction view of the medical snare according to the present invention wherein a wheel and an auxiliary pusher are connected.

<figref idref="DRAWINGS">FIG. 3</figref> is a cross-sectional view showing a state in which the auxiliary pusher is connected to a connecting pipe in part A of <figref idref="DRAWINGS">FIG. 2</figref>.

<figref idref="DRAWINGS">FIG. 4</figref> is a cross-sectional view showing a state in which a wheel and the auxiliary pusher according to the present invention are connected in part B of <figref idref="DRAWINGS">FIG. 2</figref>.

<figref idref="DRAWINGS">FIG. 5</figref> is a view showing drawing and inserting operations of a wire based on an operation of a movable handle of the medical snare according to the present invention.

<figref idref="DRAWINGS">FIG. 6</figref> is a perspective view showing rotation of the wire when the wheel of the medical snare according to the present invention is rotated.

<figref idref="DRAWINGS">FIG. 7</figref> is an illustrative view showing a surgical procedure of rotating a direction of a loop in order to remove a polyp growing in a large intestine in an arbitrary direction by rotating the wheel of the medical snare according to the present invention.

<figref idref="DRAWINGS">FIG. 8</figref> is a partial perspective view projecting a state in which locking protrusions of a wheel cover according to another embodiment are inserted into locked recesses of the wheel.

<figref idref="DRAWINGS">FIG. 9</figref> is an operational view showing a state in which the locking protrusions are locked in the locked recesses when the wheel is rotated.

<figref idref="DRAWINGS">FIG. 10</figref> is an illustrative view showing a surgical procedure of rotating a direction of a loop in order to remove a polyp growing in a large intestine in an arbitrary direction by rotating a wheel of a medical snare according to another embodiment of the present invention.

LISTS OF SYMBOLS USED FOR MAIN PARTS OF THE DRAWINGS

<b>10</b>: body, <b>11</b>: first space, <b>12</b>: exposed space, <b>13</b>: wheel cover, <b>14</b>: locking protrusion, <b>20</b>: movable handle, <b>21</b>: pusher, <b>22</b>: catching ball, <b>23</b>: second space, <b>24</b>: third space, <b>30</b>: tube, <b>40</b>: wire, <b>41</b>: loop, <b>50</b>: auxiliary pusher, <b>51</b>: engaging face, <b>60</b>: wheel, <b>61</b>: engaged hole, <b>62</b>: anti-slide recess, <b>63</b>: locking recess, <b>70</b>: connecting pipe, <b>71</b>: tapered end, <b>72</b>; connecting end, <b>100</b>: medical snare

BEST MODE

The present invention is configured so that the expansion direction of a loop is easily rotated in an arbitrary direction in which a removable target has grown, the removable target is easily inserted info the loop so as to allow a surgical procedure to be easily performed to reduce a time required for the surgical procedure and burdens of a patient and a surgeon, and free rotation of a wheel is prevented to be able to fix the expansion direction of the loop.

MODE FOR INVENTION

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

As shown in <figref idref="DRAWINGS">FIGS. 1 to 6</figref>, a medical snare of the present invention is configured so that a pusher <b>21</b> is coupled in front of a movable handle <b>20</b> moving along a cylindrical body <b>10</b> in a forward/backward direction, that a wire <b>40</b>, at a front end of which a loop <b>41</b> is formed, is connected to a front end of the pusher <b>21</b> along an interior of a tube <b>30</b> coupled to the front of the cylindrical body <b>10</b>, and that tissue is inserted into the loop <b>41</b> exposed from the tube <b>30</b> by forward movement of the movable handle <b>20</b> and is cut by backward movement of the movable handle <b>20</b> so as to perform a surgical procedure.

Here, the body <b>10</b> has a long cylinder shape and is provided with a first space <b>11</b> at a rear end thereof into which a thumb of an operator is inserted. Further, the body <b>10</b> is provided with spaces at a front end thereof which are open in opposite directions.

To expatiate on the body, the body <b>10</b> is integrally formed with a wheel cover <b>13</b> at the front end thereof which surrounds a wheel <b>60</b> so that a circumference of the wheel <b>60</b> is partly exposed, and one or more locking protrusions <b>14</b> protrude from an inner wall of one side of the wheel cover <b>13</b>.

In the present invention, an example in which two locking protrusions <b>14</b> are formed is described. However, three or more locking protrusions <b>14</b> may be formed.

In detail, the wheel cover <b>13</b> is formed as a track-shaped tube and has exposed spaces <b>12</b> formed in the opposite directions. The wheel cover <b>13</b> may be formed of a synthetic resin (plastic) material so as to be thin (see <figref idref="DRAWINGS">FIG. 8</figref>).

Moreover, the movable handle <b>20</b> is coupled to an outer circumference of the body <b>10</b> so as to slide along a length of the body <b>10</b> in a forward/backward direction, and is integrally formed with second and third spaces <b>23</b> and <b>24</b> which are disposed so as to face each other and into which index and middle fingers are inserted.

In this case, an auxiliary pusher <b>50</b>, on an outer circumference of which engaging faces <b>51</b> are formed, is rotatably coupled to a front end of the pusher <b>21</b> of the movable handle <b>20</b>.

These engaging faces <b>51</b> of the auxiliary pusher <b>50</b> are horizontally parallel with each other, and thus the other faces are formed as a round track.

Here, to rotate the auxiliary pusher <b>50</b> relative to the pusher <b>21</b>, the front end of the pusher <b>21</b> is provided with a catching ball <b>22</b> whose diameter is larger than that of the pusher <b>21</b>.

Further, a connecting pipe <b>70</b> is configured so that one end thereof functions as a tapered end <b>71</b> through which the pusher <b>21</b> is to pass and on which the catching ball <b>22</b> is caught, and so that the other end thereof functions as a connecting end <b>72</b> having a greater diameter than the catching ball <b>22</b>.

Meanwhile, the auxiliary pusher <b>50</b> is fixedly connected to the connecting end <b>72</b> of the connecting pipe <b>70</b>.

When the auxiliary pusher <b>50</b> is rotated, the auxiliary pusher <b>50</b> and the connecting pipe <b>70</b> are configured to be rotated without being separated from the pusher <b>21</b>.

Further, the wire <b>40</b> having the loop <b>41</b> is fixedly coupled to a front end of the auxiliary pusher <b>50</b>.

Furthermore, the wheel <b>60</b>, in the center of which a engaged hole <b>61</b> is formed so as to be fitted around an outer circumference of the auxiliary pusher <b>50</b>, is installed on the front end of the body <b>10</b> so as to not be separated.

In this case, anti-slide recesses <b>62</b> are formed along the outer circumference of the wheel <b>60</b> so as to prevent fingers from sliding when the wheel <b>60</b> is rotated.

In addition, a plurality of locked recesses <b>63</b> into which the locking protrusions <b>14</b> are inserted and locked are formed in an outer wall of one side of the wheel <b>60</b> in a circumferential direction of the wheel <b>60</b>.

These locked recesses <b>63</b> are recessed in a shape in which the locking protrusions <b>14</b> can be inserted. In the present invention, eight locked recesses <b>63</b> are given as an example.

In the medical snare <b>100</b> of the present invention, when the movable handle <b>20</b> moves forward/backward, the auxiliary pusher <b>50</b> slidably passes through the engaged hole <b>61</b> of the wheel <b>60</b>. Then, when the wheel <b>60</b> is rotated, the auxiliary pusher <b>50</b> and the wire <b>40</b> are rotated so as to be able to switch an open direction of the loop <b>41</b> due to engagement of the engaging faces <b>51</b> and the engaged hole <b>61</b>.

An operation and effects of the medical snare configured as described above will be described below.

As shown in <figref idref="DRAWINGS">FIGS. 1 to 7</figref>, a surgical procedure of removing a polyp <b>200</b> such as cyst as a spot to be operated on from the large intestine using the medical snare <b>100</b> will be described as an example.

To use the medical snare <b>100</b> for the surgical procedure, the movable handle <b>20</b> is pulled fully backward so that the loop <b>41</b> is compressed and inserted into the tube <b>30</b>.

In this state, the tube <b>30</b> is inserted, into the large intestine through the anus along with an endoscope (not shown).

Then, when a position of the polyp <b>200</b> is identified through the endoscope, the thumb is inserted into the first space <b>11</b> of the body <b>10</b>, and the index and middle fingers are respectively inserted into the second and third spaces <b>23</b> and <b>24</b> of the movable handle <b>20</b> so as to grasp the medical snare <b>100</b> with one hand.

Next, the hand grasping the medical snare <b>100</b> is stretched so that the body <b>10</b> and the movable handle <b>20</b> move away from each other, and thereby the loop <b>41</b> is exposed from the tube <b>30</b> while being expanded.

Here, when the movable handle <b>20</b> moves along the body <b>10</b> in a forward direction, the catching ball <b>22</b> of the pusher <b>21</b> pushes the rear end of the auxiliary pusher <b>50</b>. Thus, the auxiliary pusher <b>50</b> and the wire <b>40</b> are pushed forward together, and the loop <b>41</b> is exposed from the interior to the exterior of the tube <b>30</b>.

Further, the engaging faces <b>51</b> of the auxiliary pusher <b>50</b> slides in the engaged hole <b>61</b> of the wheel <b>60</b>, and the connecting pipe <b>70</b> is located at the rear of the wheel <b>60</b>.

In this way, when the loop <b>41</b> is exposed from the tube <b>30</b>, an operator inserts the polyp <b>200</b> into an expanded space <b>41</b><i>a </i>of the loop <b>41</b>. In this state, the operator closes the hand grasping the medical snare <b>100</b> so that the body <b>10</b> and the movable handle <b>20</b> move toward each other.

That is, the loop <b>41</b> is pulled into the tube <b>30</b> under pressure, and cuts and removes the polyp <b>200</b>.

When a position at which the polyp <b>200</b> has grown is not coincident with the expanded space <b>41</b><i>a </i>of the loop <b>41</b>, the wheel <b>60</b> is rotated in a leftward/rightward direction using the other hand with the medical snare <b>100</b> grasped with one hand. Thus, the auxiliary pusher <b>50</b> and the wire <b>40</b> are rotated together since the engaging faces <b>51</b> of the auxiliary pusher <b>50</b> are engaged in the engaged hole <b>61</b> of the wheel <b>60</b>.

This is because the diameter of the connecting end <b>72</b> of the connecting pipe <b>70</b> coupled with the auxiliary pusher <b>50</b> is greater than that of the catching ball <b>22</b> of the pusher <b>21</b>.

In this way, the expanded space <b>41</b><i>a </i>of the loop <b>41</b> of the wire <b>40</b> is rotated in a direction in which the polyp <b>200</b> is easily inserted by the rotation of the wheel <b>60</b>, so that the polyp <b>200</b> growing in any direction can be easily inserted into the expanded space <b>41</b><i>a </i>of the loop <b>41</b>.

Here, when the wheel <b>60</b> is rotated to pivot the expanded space <b>41</b><i>a </i>of the loop <b>41</b>, the locking protrusions <b>14</b> of the wheel cover <b>13</b> are inserted into the locked recesses <b>63</b> of the wheel <b>60</b>. Thus, the loop <b>41</b> is not rotated to its original position by a restoring force of the wire <b>40</b>, and the rotated position of the wheel <b>60</b> is fixed. In detail, the wheel cover <b>13</b> is formed of a synthetic resin (plastic) material so as to be thin. Thereby, when the wheel <b>60</b> is rotated and thus a portion other than the locked recesses <b>63</b> passes through the locking protrusions <b>14</b> in contact with the locking protrusions <b>14</b>, the wheel cover <b>13</b> is pushed outward. Then, when the locking protrusions <b>14</b> are inserted into the locked recesses <b>63</b>, the wheel cover <b>13</b> is restored to its original position by its own elastic force.

As a result, the surgical procedure is easily performed with no inconvenience of fixing the wheel <b>60</b> so as to prevent the wheel <b>60</b> from being rotated to fix the pivoted position of the expanded space <b>41</b><i>a </i>of the loop <b>41</b> (see <figref idref="DRAWINGS">FIGS. 8</figref>, <b>9</b>, and <b>10</b>).

Further, since the engaging faces <b>51</b> of the auxiliary pusher <b>50</b> are engaged in the engaged hole <b>61</b> of the wheel <b>60</b>, the wheel <b>60</b> does not slide when rotated, so that the wheel <b>60</b> can be accurately rotated to pivot the expanded space <b>41</b><i>a </i>of the loop <b>41</b>.

Although the exemplary embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims.